At least 12 people were killed and 50 injured when a man went into an Aurora, Colorado movie theater during a midnight screening of ‘The Dark Knight Rises’ Friday morning, fired tear gas and began shooting.

Ten people reportedly died in the theater near the Aurora Mall and two more passed away in local hospitals. Initially, police said 14 people had died, but only 12 have been confirmed. In addition to injuries sustained from gunshots, a mortician said several people were hurt by a scrap metal pepper bomb.

Gunshots were fired in one theater, but bullets pierced the walls of an adjoining theater and injured people there as well.

More than 250 officers were called onto the scene in response to the violent episode. One of the injured is reportedly three months old.

Authorities say they have arrested a 24-year-old suspect who was apprehended with a pair of weapons on him, including a rifle and a handgun. The man has been identified as James Holmes. Police also said they discovered another weapon, but would not disclose what it was.

Holmes mentioned having bombs in his home, and when authorities investigated, they discovered his apartment was booby-trapped. “We are trying to determine how to disarm the flammable or explosive material,” said Aurora Police Chief Daniel Oates. “We could be here for hours or days. The pictures are fairly disturbing. It looks very sophisticated, how it’s booby-trapped. It could be a very long wait.”

Holmes reportedly wore a bulletproof vest and a mask during his rampage. Meanwhile, a San Diego woman who says she is Holmes’ mother expressed little surprise with his behavior. “You have the right person,” she said, apparently speaking on gut instinct. “I need to call the police… I need to fly out to Colorado.”

Upon learning about the incident, President Obama said he was “shocked and saddened.”